NASHUA — For sixth-grader Sam Bean, the best part of summer science camp is the experiments.

"You get to show what you can do," said Sam, who has been learning how sugar crystallizes into rock candy and how to design a catapult that can potentially outperform a slingshot.

Sam is one of 300 elementary and middle school students spending their hot summer mornings this month in the Nashua School District's Summer Sizzlers Science Academy, a four-week summer camp that challenges students with a range of science and engineering projects.

"We had a summer remediation program that was largely taught in the same way as subjects are taught throughout the year," said Superintendent Mark Conrad, who decided a couple of years ago to add a little excitement to the program.

"We chose science as the vehicle," said Conrad, adding that the summer program still reinforces literacy and math skills but also now generates interest among kids for science and engineering.

Birch Hill Elementary School teacher Randy Calhoun, director of the Summer Science Academy, said the program has grown quickly over the past three years.

"The first year, I had some recruits, but I was scrambling to fill classes," said Calhoun. "Now, the camp is filled by the early deadline for registration."

And that's probably because most of the kids in the science academy seem to be having a great time with science.

While the recent bout of extreme heat has inspired people all over the country to try to cook eggs on city sidewalks, the science academy students were taking a more sophisticated approach to cooking with summer heat. Students built solar ovens and were in the parking lot at Fairgrounds Middle School this week cooking up pizza and S'mores.

They also learned how to make rock candy, how yeast works, how roller coasters pick up speed and how to harness the power of magnets.

"We give students a lot of material and a challenge," said Deb Couture, a science teacher at Fairgrounds Middle School who also works with the summer science campers. "The students experiment and ask their own questions."

Calhoun said that approach is in sync with Nashua's emphasis on inquiry-based science.

"We give a lot more weight to students' questions," said Calhoun. "Teachers are more facilitators than teachers."

And the kids, who are given the opportunity to follow their interests and observations, rise to the occasion.

"Kids have a ton of questions and a lot of ideas — and misconceptions — about how the world works," said Calhoun. The camp offers them a chance to investigate and test their ideas and assumptions according to facts and data.

And according to Bean and other kids in the program, the projects and experiments involve a lot of cool stuff that kids want to know.

"It's really fun because of what we do," said Isabella Vincent, 9, who was loading a ball into a trechuchet, a French version of a catapult.

Calhoun said the camp has been a great way to avoid the summertime backsliding that affects reading and math skills.

"We are still teaching literacy, but the camp is a great way to expose kids to something extra," he said.

Student scientists also have a chance to visit nearby science exhibits and museums such as the Boston Museum of Science and the Ecotarium in Worcester, Mass.

Calhoun said the teachers do an amazing job of drawing kids into subjects.

"The talent of the teachers in getting kids to think and investigate problems is fantastic," he said.

Sam Bean agreed with teachers and administrators that the Summer Sizzlers Science Academy is a good way to keep up in school.

"I'm getting ahead for middle school," he said.

But for Sam and other kids, there are even bigger payoffs from summer science camp.

"I'm meeting new friends, and we're doing things that are interesting and fun," he said.